[PATCH v2 03/12] powerpc/book3s64/pkeys: Move pkey related bits in the linux page table

Aneesh Kumar K.V aneesh.kumar at linux.ibm.com
Sat May 2 21:13:38 AEST 2020 

To keep things simple, all the pkey related bits are kept together
in linux page table for 64K config with hash translation. With hash-4k
kernel requires 4 bits to store slots details. This is done by overloading
some of the RPN bits for storing the slot details. Due to this PKEY_BIT0 on
the 4K config is used for storing hash slot details.

64K before

|....|RSV1| RSV2| RSV3 | RSV4 | RPN44| RPN43   |.... | RSV5|
|....| P4 |  P3 |  P2  |  P1  | Busy | HASHPTE |.... |  P0 |

after

|....|RSV1| RSV2| RSV3 | RSV4 | RPN44 | RPN43   |.... | RSV5 |
|....| P4 |  P3 |  P2  |  P1  | P0    | HASHPTE |.... | Busy |

4k before

|....| RSV1 | RSV2     | RSV3 | RSV4 | RPN44| RPN43.... | RSV5|
|....| Busy |  HASHPTE |  P2  |  P1  | F_SEC| F_GIX.... |  P0 |

after

|....| RSV1    | RSV2| RSV3 | RSV4 | Free | RPN43.... | RSV5 |
|....| HASHPTE |  P2 |  P1  |  P0  | F_SEC| F_GIX.... | BUSY |

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
---
 arch/powerpc/include/asm/book3s/64/hash-4k.h  | 16 ++++++++--------
 arch/powerpc/include/asm/book3s/64/hash-64k.h | 12 ++++++------
 arch/powerpc/include/asm/book3s/64/pgtable.h  | 17 ++++++++---------
 3 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
index f889d56bf8cf..082b98808701 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
@@ -34,11 +34,11 @@
 #define H_PUD_TABLE_SIZE	(sizeof(pud_t) << H_PUD_INDEX_SIZE)
 #define H_PGD_TABLE_SIZE	(sizeof(pgd_t) << H_PGD_INDEX_SIZE)
 
-#define H_PAGE_F_GIX_SHIFT	53
-#define H_PAGE_F_SECOND	_RPAGE_RPN44	/* HPTE is in 2ndary HPTEG */
-#define H_PAGE_F_GIX	(_RPAGE_RPN43 | _RPAGE_RPN42 | _RPAGE_RPN41)
-#define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
-#define H_PAGE_HASHPTE	_RPAGE_RSV2     /* software: PTE & hash are busy */
+#define H_PAGE_F_GIX_SHIFT	_PAGE_PA_MAX
+#define H_PAGE_F_SECOND		_RPAGE_PKEY_BIT0 /* HPTE is in 2ndary HPTEG */
+#define H_PAGE_F_GIX		(_RPAGE_RPN43 | _RPAGE_RPN42 | _RPAGE_RPN41)
+#define H_PAGE_BUSY		_RPAGE_RSV1
+#define H_PAGE_HASHPTE		_RPAGE_PKEY_BIT4
 
 /* PTE flags to conserve for HPTE identification */
 #define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | \
@@ -59,9 +59,9 @@
 /* memory key bits, only 8 keys supported */
 #define H_PTE_PKEY_BIT4	0
 #define H_PTE_PKEY_BIT3	0
-#define H_PTE_PKEY_BIT2	_RPAGE_RSV3
-#define H_PTE_PKEY_BIT1	_RPAGE_RSV4
-#define H_PTE_PKEY_BIT0	_RPAGE_RSV5
+#define H_PTE_PKEY_BIT2	_RPAGE_PKEY_BIT3
+#define H_PTE_PKEY_BIT1	_RPAGE_PKEY_BIT2
+#define H_PTE_PKEY_BIT0	_RPAGE_PKEY_BIT1
 
 
 /*
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index 0a15fd14cf72..f20de1149ebe 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -32,15 +32,15 @@
  */
 #define H_PAGE_COMBO	_RPAGE_RPN0 /* this is a combo 4k page */
 #define H_PAGE_4K_PFN	_RPAGE_RPN1 /* PFN is for a single 4k page */
-#define H_PAGE_BUSY	_RPAGE_RPN44     /* software: PTE & hash are busy */
+#define H_PAGE_BUSY	_RPAGE_RSV1     /* software: PTE & hash are busy */
 #define H_PAGE_HASHPTE	_RPAGE_RPN43	/* PTE has associated HPTE */
 
 /* memory key bits. */
-#define H_PTE_PKEY_BIT4	_RPAGE_RSV1
-#define H_PTE_PKEY_BIT3	_RPAGE_RSV2
-#define H_PTE_PKEY_BIT2	_RPAGE_RSV3
-#define H_PTE_PKEY_BIT1	_RPAGE_RSV4
-#define H_PTE_PKEY_BIT0	_RPAGE_RSV5
+#define H_PTE_PKEY_BIT4		_RPAGE_PKEY_BIT4
+#define H_PTE_PKEY_BIT3		_RPAGE_PKEY_BIT3
+#define H_PTE_PKEY_BIT2		_RPAGE_PKEY_BIT2
+#define H_PTE_PKEY_BIT1		_RPAGE_PKEY_BIT1
+#define H_PTE_PKEY_BIT0		_RPAGE_PKEY_BIT0
 
 /*
  * We need to differentiate between explicit huge page and THP huge
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 368b136517e0..e31369707f9f 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -32,11 +32,13 @@
 #define _RPAGE_SW1		0x00800
 #define _RPAGE_SW2		0x00400
 #define _RPAGE_SW3		0x00200
-#define _RPAGE_RSV1		0x1000000000000000UL
-#define _RPAGE_RSV2		0x0800000000000000UL
-#define _RPAGE_RSV3		0x0400000000000000UL
-#define _RPAGE_RSV4		0x0200000000000000UL
-#define _RPAGE_RSV5		0x00040UL
+#define _RPAGE_RSV1		0x00040UL
+
+#define _RPAGE_PKEY_BIT4	0x1000000000000000UL
+#define _RPAGE_PKEY_BIT3	0x0800000000000000UL
+#define _RPAGE_PKEY_BIT2	0x0400000000000000UL
+#define _RPAGE_PKEY_BIT1	0x0200000000000000UL
+#define _RPAGE_PKEY_BIT0	0x0100000000000000UL
 
 #define _PAGE_PTE		0x4000000000000000UL	/* distinguishes PTEs from pointers */
 #define _PAGE_PRESENT		0x8000000000000000UL	/* pte contains a translation */
@@ -58,13 +60,12 @@
  */
 #define _RPAGE_RPN0		0x01000
 #define _RPAGE_RPN1		0x02000
-#define _RPAGE_RPN44		0x0100000000000000UL
 #define _RPAGE_RPN43		0x0080000000000000UL
 #define _RPAGE_RPN42		0x0040000000000000UL
 #define _RPAGE_RPN41		0x0020000000000000UL
 
 /* Max physical address bit as per radix table */
-#define _RPAGE_PA_MAX		57
+#define _RPAGE_PA_MAX		56
 
 /*
  * Max physical address bit we will use for now.
@@ -125,8 +126,6 @@
 			 _PAGE_ACCESSED | _PAGE_SPECIAL | _PAGE_PTE |	\
 			 _PAGE_SOFT_DIRTY | _PAGE_DEVMAP)
 
-#define H_PTE_PKEY  (H_PTE_PKEY_BIT0 | H_PTE_PKEY_BIT1 | H_PTE_PKEY_BIT2 | \
-		     H_PTE_PKEY_BIT3 | H_PTE_PKEY_BIT4)
 /*
  * We define 2 sets of base prot bits, one for basic pages (ie,
  * cacheable kernel and user pages) and one for non cacheable
-- 
2.26.2

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